(First upload on December 27 2004. Last on March 27 2024) [ 日本語 | English ]

Juncus effusus L. var. decipiens Buchen.

Mount Usu / Sarobetsu post-mined peatland
From left: Crater basin in 1986 and 2006. Cottongrass / Daylily

Juncus L. (イグサ)
I (or Hime-i) (イ/ヒメイ, 藺/姫藺), lamp rush, common rush, or soft rush
Toushinsou (トウシンソウ, 燈心草)
Lifeform: perennial rush wtih 70-100 cm in height, shorter on Mount Koma (Titus & Tsuyuzaki 2003)
Flowering: June-October
Habitat: wet meadows, shallows
Fruit: 3 chambers (green-brown) ↔ J. setchuensis: 1 chamber (3 septa)

Juncus decipiens (Buchenau) Nakai

f. utilis Makino (コヒゲ): utilzed for bale and matting
Morphology: highly variable
Classified by USDA
var. brunneus Engelm., lamp rush
var. conglomeratus (L.) Engelm., common rush
var. decipiens Buchenau., lamp rush: distributed in Japan
var. effusus., common rush, or soft rush: the type, distributed in Europe, West Siberia and North America
var. exiguus Fernald et Wiegand., lamp rush
var. gracilis Hook., lamp rush
var. pacificus Fernald et Wiegand., Pacific rush
var. pylaei (Laharpe) Fernald et Wiegand., common rush
var. solutus Fernald et Wiegand., lamp rush

Juncus effusus in Hokkaido

[1/2] along a stream near Onnenai Visitor Center in Kushiro Moor, eastern Hokkaido, on July 2 2014. [3] near Horonai River in Tomakomai Experimental Forest on June 25 2012. [4] beside Fureai-no-yu spa, Toyotomi Spa, northern Hokkaido, on May 28 2019. [5] on Makomanai skislope, South Ward, Sapporo, on July 6 1985. The specimen is kept in SAPS.


Mount Usu and Mount Koma

[1] grown in a greenhouse, CAST, HU, on December 24 2008. [2] on March 7 2009. The soil samples were collected from the former topsoil on Mount Usu. The high seed densities were confirmed 10, 20 and 30 years after the eruptions (Tsuyuzaki 1991, Tsuyuzaki & Goto 2001, Tsuyuzaki 2010).

Seeds1 Seeds2 Seeds3
[1/2] These seeds were extracted from the former topsoil by a floation method in the fall of 2008. [3] at December 19, 2004, two days after imbibition. Seeds were collected during 8th and 9th, September, 2004, by C. Miyoshi. (Tsuyuzaki & Miyoshi 2009)

cv spiralis (ラセンイ)
[1-2] in a large garden store, Sapporo, on November 4 2017.